Hardback books usually comprise a pair of rigid or semi-rigid planar cover boards which, when the book is closed, cover the front and back leaves of the book respectively. Usually, the book comprises a plurality of sections, sometimes called signatures, gatherings or bundles, each section comprising a plurality of leaves. The sections are connected together at the rear of the book so as to form a spine. The leaves of each section are folded along a fold-line which extends along the spine of the book. The sections may be held together by any combination of glue, guards, and stitching. In addition, binding cords or tapes may be provided, each binding cord extending laterally across the spine in order to provide the spine with additional strength and rigidity, and as a sewing support.
The two cover boards are effectively hinged to the leaves of the book about two axes extending along the two longitudinal edges of the spine. For example, the cover boards may be attached to the guards attached to the front and back sections of the book so as to form cover hinges along the front and back edges of the spine. The cover boards are typically covered with a protective covering material which extends between the two cover boards across the spine of the book so as to form a spine covering. The spine covering is not usually attached to the spine of the book, but nevertheless prevents easy access to the rear edges of the sections. In some cases, particularly in hand-bound styles, under-linings or coverings of acid-free material may be directly attached to the spine folds. This can make it particularly difficult to restore the book, since the sections of the book cannot easily be separated and re-connected. The ease with which a book can be taken apart in order to allow restoration is known in the art as reversibility. It will therefore be seen that the known hardback books described above are not particularly reversible.
A further problem with the known hardback books described above is that, because the spine covering can come into contact with the spine of the book, there is a tendency for acid to migrate through the spine covering and attack the spine. The acid can increase the rate of deterioration of the sewing and sections, and the problem is particularly noticeable in the case of flexible leather spine coverings.
The invention seeks to overcome the disadvantages of the prior art.